Wednesday, April 29, 2009

Ergonomics

Ergonomics is the science of designing the job, equipment, and workplace to fit the worker. Proper ergonomic design is necessary to prevent repetitive strain injuries, which can develop over time and can lead to long-term disability.[1]

Ergonomics is the scientific discipline concerned with designing according to human needs, and the profession that applies theory, principles, data and methods to design in order to optimize human well-being and overall system performance. [2] The field is also called human engineering, and human factors.

Ergonomic research is performed by those who study human capabilities in relationship to their work demands. Information derived from these studies contributes to the design and evaluation of tasks, jobs, products, environments and systems in order to make them compatible with the needs, abilities and limitations of people.[3]

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World-systems approach

The World-systems approach is a post-Marxist view of world affairs, one of several historical and current applications of Marxism to international relations.

One of the basics of the approach is its view of imperialism, which for many Marxists during the 20th century represented "the highest stage of capitalism", a term coined by Vladimir Lenin, who also used the terms periphery and core as a means to analyze world politics and economy.

Immanuel Wallerstein, a leading advocate of the approach, uses the same terminology. He characterizes the world system as a set of mechanisms which redistributes resources from the periphery to the core. In his terminology, the core is the developed, industrialized, democratic part of the world, and the periphery is the underdeveloped, raw materials-exporting, poor part of the world; the market being the means by which the core exploits the periphery.

Wallerstein traces the origin of today's world-system to the 16th century in Western Europe, and defines it as:

"...a social system, one that has boundaries, structures, member groups, rules of legitimation, and coherence. Its life is made up of the conflicting forces which hold it together by tension and tear it apart as each group seeks eternally to remold it to its advantage. It has the characteristics of an organism, in that it has a life-span over which its characteristics change in some respects and remain stable in others. One can define its structures as being at different times strong or weak in terms of the internal logic of its functioning."[1]

Apart of these, Wallerstein defines four temporal features of that. Cyclical rhythms represent the short-term fluctuation of economy, while secular trends mean deeper long run tendencies, such as general economic growth or decline. In the theory the term contradiction means a general controversy in the system, usually concerning some short-run vs. long run trade-offs. For example the problem of underconsumption, wherein the drive-down of wages increases the profit for the capitalists on the short-run, but considering the long run, the decreasing of wages may have a crucially harmful effect by reducing the demand for the product. The last temporal feature is the crisis: a crisis occurs, if a constellation of circumstances brings about the losing of the system's structure, which also means the end of the system.

Technically speaking, World-systems analysis is not a theory, but an approach to social analysis and social change. It is based in part on the works of Samir Amin, Giovanni Arrighi, Andre Gunder Frank, and Immanuel Wallerstein with major contributions by Christopher Chase-Dunn, Volker Bornschier, Peter Turchin, Andrey Korotayev, Janet Abu Lughod, Thomas D. Hall, Kunibert Raffer, David Wilkinson, and others.

It should be noted that World-systems analysis is not only derived from the neo-Marxist literature on development but also from the French Annales School tradition(especially Fernand Braudel).

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Systems theory

Systems theory is an interdisciplinary field of science and the study of the nature of complex systems in nature, society, and science. More specifically, it is a framework by which one can analyze and/or describe any group of objects that work in concert to produce some result. This could be a single organism, any organization or society, or any electro-mechanical or informational artifact. Systems theory first originated in biology in the 1920s out of the need to explain the interrelatedness of organisms in ecosystems.[1] As a technical and general academic area of study it predominantly refers to the science of systems that resulted from Bertalanffy's General System Theory (GST), among others, in initiating what became a project of systems research and practice.

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Ecosystem ecology

Figure 1. A riparian forest in the White Mountains, New Hampshire (USA).

Ecosystem ecology is the integrated study of biotic and abiotic components of ecosystems and their interactions within an ecosystem framework. This science examines how ecosystems work and relates this to their components such as chemicals, bedrock, soil, plants, and animals.

Ecosystem ecology examines physical and biological structures and examines how these ecosystem characteristics interact with each other. Ultimately, this helps us understand how to maintain high quality water and economically viable commodity production. A major focus of ecosystem ecology is on functional processes, ecological mechanisms that maintain the structure and services produced by ecosystems. These include primary productivity (production of biomass), decomposition, and trophic interactions.

Studies of ecosystem function have greatly improved human understanding of sustainable production of forage, fiber, fuel, and provision of water. Functional processes are mediated by regional-to-local level climate, disturbance, and management. Thus ecosystem ecology provides a powerful framework for identifying ecological mechanisms that interact with global environmental problems, especially global warming and degradation of surface water.

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Earth systems engineering and management

Earth systems engineering and management (ESEM) is a discipline used to analyze, design, engineer and manage complex environmental systems. It entails a wide range of subject areas including anthroplogy, engineering, environmental science, ethics and philosophy. At its core, ESEM looks to "rationally design and manage coupled human-natural systems in a highly integrated and ethical fashion" [1] ESEM is a newly emerging area of study that has taken root at the University of Virginia, Cornell and other universities throughout the United States. Founders of Earth Systems Engineering & Management are Braden Allenby and Michael Gorman.[2]

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Synthetic biology

Synthetic biology is a new area of biological research that combines science and engineering in order to design and build ("synthesize") novel biological functions and systems.

A light programmable biofilm made by the UT Austin / UCSF team during the 2004 Synthetic Biology competition, displaying "Hello World"

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Perceptual control theory

Perceptual control theory (PCT) is a psychological theory of animal and Human behavior originated by maverick scientist William T. Powers. In contrast with other theories of psychology and behavior, which assume that behavior is a function of perception — that perceptual inputs determine or cause behavior — PCT postulates that an organism's behavior is a means of controlling its perceptions. In contrast with engineering control theory, the reference variable for each negative feedback control loop in a control hierarchy is set from within the system (the organism), rather than by an external agent changing the setpoint of the controller.[1] PCT also applies to nonliving autonomic systems.[2]

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Operations research

Operations Research (OR) in the USA, Canada, South Africa and Australia, and Operational Research in Europe, is an interdisciplinary branch of applied mathematics and formal science that uses methods such as mathematical modeling, statistics, and algorithms to arrive at optimal or near optimal solutions to complex problems. It is typically concerned with optimizing the maxima (profit, assembly line performance, crop yield, bandwidth, etc) or minima (loss, risk, etc.) of some objective function. Operations research helps management achieve its goals using scientific methods.

Model of Operation research study, based on Stafford Beer (1959).[1]

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Dynamical systems theory

Dynamical systems theory is an area of applied mathematics used to describe the behavior of complex dynamical systems, usually by employing differential equations or difference equations. When differential equations are employed, the theory is called continuous dynamical systems. When difference equations are employed, the theory is called discrete dynamical systems. When the time variable runs over a set which is discrete over some intervals and continuous over other intervals or is any arbitrary time-set such as a cantor set then you get dynamic equations on time scales. Some situations may also be modelled by mixed operators such as differential-difference equations.

This theory deals with the long-term qualitative behavior of dynamical systems, and the studies of the solutions to the equations of motion of systems that are primarily mechanical in nature; although this includes both planetary orbits as well as the behaviour of electronic circuits and the solutions to partial differential equations that arise in biology. Much of modern research is focused on the study of chaotic systems.

This field of study is also called just Dynamical systems, Systems theory or longer as Mathematical Dynamical Systems Theory and the Mathematical theory of dynamical systems.

The Lorenz attractor is an example of a non-linear dynamical system. Studying this system helped give rise to Chaos theory.

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Control engineering

Control systems play a critical role in space flight

Control engineering is the engineering discipline that applies control theory to design systems with predictable behaviors. The engineering activities focus on the mathematical modeling of systems of a diverse nature.

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Control theory

The concept of the feedback loop to control the dynamic behavior of the system: this is negative feedback, because the sensed value is subtracted from the desired value to create the error signal which is amplified by the controller.

Control theory is an interdisciplinary branch of engineering and mathematics, that deals with the behavior of dynamical systems. The desired output of a system is called the reference. When one or more output variables of a system need to follow a certain reference over time, a controller manipulates the inputs to a system to obtain the desired effect on the output of the system.

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Medical cybernetics

Medical Cybernetics is a field of applied cybernetics which utilizes the concepts of cybernetics to medical research and practice. It covers an emerging working program for the application of systems- and communications-theory, connectionism and decision theory on biomedical research and health related questions.

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Biocybernetics

Biocybernetics is the application of cybernetics to biological science, comprised of biological disciplines that benefit from the application of cybernetics: neurology, multicellular systems and others. Biocybernetics plays a major role in systems biology, seeking to integrate different levels of information to understand how biological systems function.

Biocybernetics as an abstract science is a part of theoretical biology, and based upon the principles of systemics.

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Complex systems

Complex systems is a scientific field which studies the common properties of systems considered complex in nature, society and science. It is also called complex systems theory, complexity science, study of complex systems, sciences of complexity, non-equilibrium physics, and historical physics. The key problems of such systems are difficulties with their formal modeling and simulation. From such perspective, in different research contexts complex systems are defined on the base of their different attributes. At present, the consensus related to one universal definition of complex system does not exist yet.

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Chaos theory

A plot of the Lorenz attractor for values r = 28, σ = 10, b = 8/3

In mathematics, chaos theory describes the behavior of certain dynamical systems – that is, systems whose states evolve with time – that may exhibit dynamics that are highly sensitive to initial conditions (popularly referred to as the butterfly effect). As a result of this sensitivity, which manifests itself as an exponential growth of perturbations in the initial conditions, the behavior of chaotic systems appears to be random. This happens even though these systems are deterministic, meaning that their future dynamics are fully defined by their initial conditions, with no random elements involved, this behavior is known as deterministic chaos, or simply chaos.

Chaotic behavior is also observed in natural systems, such as the weather. This may be explained by a chaos-theoretical analysis of a mathematical model of such a system, embodying the laws of physics that are relevant for the natural system.

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Globalization

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Night view of the Pudong District of Shanghai, China
The construction of continental hotels is a major consequence of globalization process in affiliation with tourism and travel industry, Dariush Grand Hotel, Kish, Iran

Globalization (globalisation) in its literal sense is the process of transformation of local or regional phenomena into global ones. It can be described as a process by which the people of the world are unified into a single society and function together.

This process is a combination of economic, technological, sociocultural and political forces.[1] Globalization is often used to refer to economic globalization, that is, integration of national economies into the international economy through trade, foreign direct investment, capital flows, migration, and the spread of technology.[2]

Saskia Sassen writes that "a good part of globalization consists of an enormous variety of micro-processes that begin to denationalize what had been constructed as national - whether policies, capital, political subjectivities, urban spaces, temporal frames, or any other of a variety of dynamics and domains."[3]

The United Nations ESCWA has written that globalization "is a widely-used term that can be defined in a number of different ways. When used in an economic context, it refers to the reduction and removal of barriers between national borders in order to facilitate the flow of goods, capital, services and labour...although considerable barriers remain to the flow of labour...Globalization is not a new phenomenon. It began in the late nineteenth century, but its spread slowed during the period from the start of the First World War until the third quarter of the twentieth century. This slowdown can be attributed to the inwardlooking policies pursued by a number of countries in order to protect their respective industries.. however, the pace of globalization picked up rapidly during the fourth quarter of the twentieth century..."[4]

Tom G. Palmer of the Cato Institute defines globalization as "the diminution or elimination of state-enforced restrictions on exchanges across borders and the increasingly integrated and complex global system of production and exchange that has emerged as a result."[5]

Thomas L. Friedman has examined the impact of the "flattening" of the world, and argues that globalized trade, outsourcing, supply-chaining, and political forces have changed the world permanently, for both better and worse. He also argues that the pace of globalization is quickening and will continue to have a growing impact on business organization and practice.[6]

Noam Chomsky argues that the word globalization is also used, in a doctrinal sense, to describe the neoliberal form of economic globalization.[7]

Herman E. Daly argues that sometimes the terms internationalization and globalization are used interchangeably but there is a slight formal difference.The term "internationalization" refers to the importance of international trade, relations, treaties etc. International means between or among nations.

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Political psychology

Political psychology is an interdisciplinary academic field dedicated to the relationship between psychology and political science, with a focus on the role of human thought, emotion, and behavior in politics.[1]

It analyzes political science as related to entities such as voters, lawmakers, local and national governments and administrations, international organizations, political parties, and associations. While the grammar of "political psychology" tends to stress psychology as the central field, the discipline could also be accurately labeled "the psychology of politics," so as to more evenly recognize the interdisciplinary nature of the field.[2]

Also not fully conveyed by the label is the wide scope of the disciplines from which political psychology draws, including anthropology, cognitive and personality psychology, sociology, psychiatry, international relations, and other more distant fields such as economics, philosophy, and the arts.[2]

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